I tried placing an order on-line yesterday morning, website wouldn't move. Called in and they handled it over the phone. Only to have me realize they ordered the wrong phone (iPhone 5S Silver 64GB). I had to call back in and they would place a second order. Unfortunately, by the time my correct order (iPhone 6 Space Grey 64GB) was placed it went into backorder and now with a shipping timeline of 2-4 weeks as opposed to the original 7-10 days.
T-Mobile's been great to me, I've been a loyal customer for nearly a decade, but it's issues like these that make me want to change carriers.